In the field of display technology, the method for manufacturing layers in display devices includes inkjet printing, micro-transfer printing, spin-coating, or the like. When the method, such as inkjet printing, is used in manufacturing the layers, a layer solution must be dried to remove a solvent therein. Generally, the solvent is converted from liquid into gas by roasting and film forming of the layer solution via a traditional thermal evaporation process. However, due to the “coffee ring” effect, the formed layers will be thin in the middle and thick on both sides, namely the layers are non-uniform.